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<html lang="en">
<head>
  <meta charset="UTF-8">
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  <title>Document</title>
</head>
<body>
  
  <script>
    // var str = '你真好，你真 是 个潮巴'

    // console.log( str.length ) 

    // console.log( 'str' + 'ing' )  // string
    // console.log( '我' + '和' + '您' )  // 我和您

    // console.log( 'qwer' + 123 )  // qwer123

    // console.log( 10 + 20 + 'qwer')  // 30qwer

    // console.log( 'qwer' + (10 + 20) )  // qwer30

    var age = 20

    //  引引加加
    console.log('我今年' + age + '岁了')
  </script>
</body>
</html>